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The NOAA (National Oceanic and Atmospheric Administration) is an American government organisation that operates a nationwide network of radio stations. Weather service warnings and hazard forecasts are broadcast 24/7 from these stations on the VHF band from 162.400-162.550MHz. The broadcasts include warnings and post event information for earthquakes, floods, and chemical spills etc. In the event of such a disaster, the power grid and internet may well go down, leaving good old radio as the best way to receive the latest updates on a situation.

The messages transmitted by the NOAA are encoded using the SAME (Specific Area Message Encoding) protocol. Ready-made receivers are available for working with SAME messages but if you want to add a computer in to the mix, the NOAA weather receiver for the Raspberry Pi has you covered. This add-on board can pick up the NOAA transmissions and decode the SAME packets for you. A speaker is included with the option of a headphone jack instead. Two 5 amp relays are also included in case you want to trigger a really loud alarm and some lights in the event of an impending disaster.

The SAME protocol lets you pick and choose which areas and which type of emergencies you want to be alerted about. Pair this with some Python code and there are a whole host of interesting projects opened up! For more information on the NOAA weather transmissions check out http://www.nws.noaa.gov/nwr/

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The Sharp Memory LCD range comes in sizes from 0.96 inches to 4.4 inches (diagonal). What makes them special is their insanely low power consumption making them ideal for things like watches or anything you want to run on battery power for a long time. Take for example the 1.28 inch Sharp Memory LCD.  It runs on a 3V supply and only draws 12 µW to display a static image or 50 µW for a dynamic image. In theory you could display dynamic images for 6 months with a single charge of a tiny 100mAh battery (taking only the screen’s power usage into account of course).

Adding one of these displays to your project is a little tricky due to the FFC connection they use. Fortunately, the LCD breakout board designed by Kuzyatech makes things more accessible routing the FFC connector out to 0.1″ header pins. The board also has the necessary resistors and capacitors for the display populated which is one less thing for you to worry about.

With displays it’s much better to see them in action to get an idea of what they are like. Mike Harrison from mikeselectricstuff has a video all about Sharp Memory LCDs. Check it out!

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When you think of Arduino boards, you generally think of turning lights or motors on and off. With this video experimenter shield however, you can now manipulate composite video in a simple, but interesting way.

As shown in the video below, this shield allows you to do all kinds of strange effects, including overlaying a graph on the screen, or even creating an effect where you can shoot whatever is being displayed. Interestingly, the shield allows for tracking of a laser pointer, so perhaps one could make a very simple version of Duck Hunt with it.

It also has the capability of using the video signal as an input, letting the Arduino board do simple computer vision tasks or even decode closed captions.

If interfacing with video isn’t really your thing, creator Nootropic Designs has several other interesting boards available, mostly dealing with audio manipulation. Most of Nootropic’s designs, including the board featured here, are available in kit form or assembled.

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If the normal guitar effects pedals aren’t cutting it, and you want something truly unique, perhaps you’d like to make your own. Hooking components up on a solderable breadboard can be a challenge, but what about the housing? The last thing you want when you’re thrashing in front of thousands of fans is for your circuit board to crack under the weight of your boot!

Fortunately, thanks to Tindie seller Rixen, you can now buy a a cast aluminum model with nothing inside, ready for your homebrew electronics. They’re priced at just under $40 for an unpainted and undrilled enclosure. Or for around five dollars more, you can get it powder coated. Given my general impatience for painting, and how good powder coating can look, I’d see that as a bargain. Check out the pedal in the video below:

Although I don’t play guitar, this blank pedal setup really has my mind going. Perhaps it could be adapted for video games, or any other use where you need a foot interface for your electronics!

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Small notebooks and tablet computers are wonderful things. You can easily stuff them into a backpack and use them for browsing your media, playing games, or even to work on the go. Unfortunately, trying to put all this computing power into a small form factor means that some accessories, like USB ports, are at a premium or neglected all together.

To solve this dilemma, Tindie seller Mux decided to do something about it with this tiny USB hub. As seen on the video below, this simple 1 port to 2 port hub measures only 12 x 10mm, small enough to fit on a single keyboard key, and can be embedded in what little space is left on a tablet. Or at least the Cube i7 Stylus tablet which he’s using; I’d have to guess even this little guy wouldn’t fit in an iPad!

Besides showing off the process of stuffing this guy into a tablet, another interesting tidbit in the video comes around 8:30, where he shows how these tiny hubs come from the manufacturer. These boards are so small, that he is able to print six of them on the 5cm x 5cm “panels” that his board house offers as a special, saving him significant manufacturing costs.

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As Tindie blog readers, I’m certain that you all create strong passwords for each and every one of your accounts, perhaps even using a Mooltipass to keep track of everything. If, however, a friend of yours uses his cat’s name followed by “123” for each account, then perhaps it’s time to get one of these mechanical password keepers.

This password keeping cylinder works by sliding each of its four rings around until you spell the name of the site. Each of these letters produces a pseudorandom symbol, which can then be input as the first part of a site’s password (actually the line above it according to the video below). After this, you can make up a rule to fill out the rest of the password, generating something that is, for practical purposes, impossible to guess.

One possible flaw in this design that you might notice is that if everyone gets the same key ring, than anyone with the special “decoder” can produce the first four symbols of your password. This device has that covered, in that there are eight rings available, and they can be rearranged how you see fit.

If that weren’t enough, I’d like to point out that it is hollow and has a tiny bit of space inside for a “lost and found” note (or for whatever else you might want to store inside). And for those of you who are truly mechanical nerds, it’s quite reminiscent of the CURTA mechanical calculator. Awesome.

Also, be sure to check out the rest of the Russtopia Labs store for more password-related goodness!

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Logging sensor values over the course of days or weeks on a single battery charge is a lot easier said than done. The BLEthrowie made by Singleton Labs is a compact data logger which uses the CC2541 System-on-chip made by Texas Instruments. This tiny SOC contains an MCU and Bluetooth Low Energy. The chip itself is thankfully not too power hungry, drawing only 0.5uA in sleep mode and 18.2mA while transmitting a message via Bluetooth.

Singleton labs has not explicitly provided any use cases along with an expected battery life but they mention it being possible to log hourly for a week on a single battery charge. They don’t tell us how frequently the BLEThrowie is transmitting its sensor values via Bluetooth though which makes the information less useful. With a liberal use of low power mode and only transmitting a few times per day, it is in theory possible to get a few weeks of data logging on a single charge.

A big aspect of the usefulness of this Bluetooth sensor board is the Android/iOS apps written to go along with it. These apps are written to display graphs of sensor values stored in the BLEThrowie, meaning you don’t have to physically connect to the sensor to get your readings from it. Check out the video below from Singleton Labs.

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Since 2003 most car models come equipped with a CAN bus to let all of the on-board sensors and actuators talk to each other and/or a centralized computer. This data is continuously being sent back and forth as you drive. The data on a vehicle’s CAN bus includes things like engine RPM, current speed, lock/unlock commands for car doors, steering wheel angle, windows up/down, GPS position, battery voltage, brake pedal % pressed, fuel usage, and myriad more packets. Just think of all the cool things you can do with that information! First, you need a way to connect your computer to the CAN bus.

CANable is an open source USB-CAN adapter made by Protofusion.  The CANable adapter shows up on a computer as a virtual serial port meaning it’ll work with all the major operating systems. Some great CAN tools that are mentioned in the CANable documentation section. First is the cantact-app which lets you sniff messages on the bus and send messages (Windows and Mac only). Linux users can interface with a CAN bus using the can-utils package. For those wanting to write programs to automatically read/write the CAN bus, there is the canard library for Python which lets you quickly and easily start interfacing with CAN.

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If you commit unintentional herbicide more than you’d like, there’s a good chance it’s because you’re watering your plant an inappropriate amount. If this is you, or if you just can’t stand to have something natural in your house without a bit of technology attached, then the Chirp! plant watering alarm may be for you!

As described in its writeup, “You put it into the soil near a plant and it emits a tiny chirp when the soil is dry, reminding you to water the plant.” At this point, you will water the plant — yes to keep it alive, but more to stop the sound. It is, however, programmed not to chirp at night, so it should be less annoying than some other household alarms.

If the design doesn’t work for you, it’s open source, so you can make changes as needed. As is though, it should be easy enough to use for even the worst gardeners. Be sure to check out Catnip Electronics’ page for a slightly different version of this sensor, a couple of other electronics bits, and a black-and-white picture of a computer scientist with a cat’s head!

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In the world of hobbyist electronics most people are accustomed to 3.3V or 5V level logic signals. Step into the world of industrial electronics and they tend to use 24V logic signals. PLCs (Programmable Logic Controllers) work with 24V I/O but they cost anywhere from several hundred to a couple of thousand euros. The reason they are so expensive is partly due to the fact that they are built to last for years and are very reliable, but basically all they are is a microcontroller with some level shifting circuitry built in.

The VM1AT_R1 Industrial Microcontroller board made by Tutan takes the basic idea behind a PLC and puts it into a nice barebones PCB. On the board you have an ATmega328p and several shift register chips which handle all of the inputs and outputs. The board can be powered from 9-30VDC thanks to the LM2596 DC-DC switch mode power supply module. Since all of the I/O pins are done using shift registers, you get 16 digital inputs and 7 digital outputs that can operate at 24V.

Are you in need of an industrial board to read some sensors and switch some outputs but don’t want to shell out for a PLC?. This board will let you do most things a traditional PLC can do for a fraction of the price.

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